Buoyancy control system and devices employing same



U8-15,1967 Y P. R. GIMBL 3,335,685

BUOYANCY CONTROL SYSTEM AND DEVICES EMPLOYING SAMEl P. R. GIMBEL Aug.ll15, 1967 BUOYANCY CONTROL SYSTEM AND DEVICES EMPLOYING SAME Filed Oct.22, 1965 2 Sheets-Sheet L? IIIIII 4.0

NVENTOR. ,l Pfff/9 E @Mea WM? M United States Patent O 3,335,685BUOYANCY CUNTRL SYSTEM AND DEVICES EMPLOYING SAME Peter R. Gimhel, NewYork, N.Y., assigner to Blue Meridian Company, Inc., New York, N.Y., acorporation of New York Filed (ict. 22, 1965, Ser. No. 501,953 13Claims. (Cl. 114-16) This invention relates to a buoyancy control systemand to devices employing the same. More particularly, this inventionrelates to a buoyancy control system which is Iadjustable such thatapparatus embodying the buoyancy control system can be maintained at agiven depth beneath the surface of a body of water, such as beneath thesurface of the ocean.

In accordance with one embodiment of the invention there is provided aprotected submarine observation cage, such as an anti-shark cage, to thetop of which is fixed the buoyancy control system of this invention sothat the operator of the anti-shark cage can adjust and stabilize thedepth of the anti-shark cage at any suitable and useful depth beneaththe surface of the ocean.

In accordance with yet another embodi-ment of this invention there isprovided a free body or device to which the buoyancy control system ofthis invention is fixed rsuch that said free body or device can bemaintained at a `desired depth beneath the surface of a body of water.

Buoyancy control systems are known and have been employed heretofore insubmarines and other underwater vehicles and the like. For the -mostpart, the buoyancy control systems known heretofore are very complicatedin operation, particularly when embodied in submarines. Some buoyancycontrol systems, however, are simple, but in operation, because of thesimplicity, the attention of the operator is substantially alwaysrequired to maintain the system operative and/or at a desired dept-h.Also, some buoyancy control systems make the operator a virtual prisonerof the system in the sense that the operator is almost a functional partof the system with the result that without the operator taking part oractively controlling the system, the system would tend to fail. One suchsimple buoyancy control system is disclosed in U.S. Patent 3,190,256.The buoyancy control system disclosed in this patent makes the operatora virtual prisoner of the system and almost a functional part thereof.

It is an object of this invention to provide an improved buoyancycontrol system.

It is another object of this invention to provide a buoyancy controlsystem capable of attachmentto and utilization with substantially anybody or device.

Still another object of this invention is to provide a buoyancy controlsystem capable of attachment to substantially any body or `device anduseful for maintaining said body or device -at a ygiven depth beneaththe surface of a body of water.

In accordance with a very special embodiment it is an object of thisinvention to provide an improved antishark cage.

How these and other objects of this invention are achieved will becomeapparent in the light of the accompanying disclosure and drawingswherein:

FIG. 1 illustrates in cross section the buoyancy control -chamber of thebuoyancy control system of this nvention;

FIG. 2 schematically illustrates the overall buoyancy control system inaccordance with this invention;

FIG. 3 is a top perspective View of an anti-shark cage having associatedtherewith and embodied therein the buoyancy control system of thisinvention; and wherein FIG. 4 is a fragment-ary cross sectional viewtaken along lines 4 4 of FIG. 3.

ICC

In the buoyancy control system in accordance with this invention thebuoyancy of the system is dependent upon the size of an air bubbleprovided with a freeflooding buoyancy chamber. By con-trolling the sizeof the air bubble Within the buoyancy chamber of the system, thebuoyancy of the system is controlled, a larger size air b-ubble withinthe buoyancy chamber imparts greater buoyancy to the system and asmaller air bubble within the buoyancy chamber imparts relatively lessbuoyancy to the system.

The size of the air bubble within the buoyancy chamber is controlled bymeans of an adjustable water level sensing means provided within thebuoyancy chamber. The water level sensing means is operatively connectedto an air supply means and is effective to introduce air into thebuoyancy chamber from the air supply means when the water at theair-water interface of the bubble within the chamber contacts the waterlevel sensing means. Accordingly, in the operation of the buoyancycontrol system in accordance with this invention whenever the waterlevel sensing means contacts the water at the bubble air-water interfacewithin the chamber, air is introduced into the buoyancy chamber toincrease the size of the air bubble therein with resulting increase inbuoyancy of the sys-tem.

In the buoyancy control system in `accordance with this inventionwhenever it is desired to reduce the buoyancy of the system, or the sizeof the air bubble Within the buoyancy chamber, air is discharged fromthe bubble and the buoyancy chamber -to the outside, surroundingenvironment. Specifically, in accordance with this invention air isdischarged from the air bubble by fluid .conduit means communicatingbetween the interior of the buoyancy chamber and the environmentsurrounding the chamber.

In accordance with one embodiment of this invention the iluid conduitmeans is provided with. an opening. When the opening is exposed to theair at or above the air-water interface of the bubble within thebuoyancy chamber, yair is discharged from the air bubble Via the openingand the fluid conduit means into the surrounding environment, therebyreducing the size of the air bubble within the buoyancy chamber and thebuoyancy of the system.

In accordance with the special embodiment of the invention illustratedin FIG. l of the 4drawings the water level sensing means is xed to thefluid conduit means, the water level sensing means being spaced abovethe upper edge of the opening provided by said fluid conduit means, suchthat by vertically moving; the fluid conduit means within the chamberthe size of the air bubble within the chamber can be altered. If thefluid conduit means is moved upwardly within the buoyancy chamber, toeX- pose the opening of the fluid conduit means to the air within theair bubble, air is discharged via the uid conduit means into thesurrounding environment, the size of the air bubble thereby beingreduced with resulting reduction in the buoyancy of the system.

By moving the fluid conduit means downwardly within the buoyancy chamberthe water level sensing means is brought into contact with the Water ator below 4the air-water interface of the bubble. 'Ihe water levelsensing means upon contacting water causes yair to be discharged intothe buoyancy chamber to increase the size of the air bubble with theresulting increase in the buoyancy of the system.

By controlling the vertical distance separating the water level sensingmeans and the upper edge of the opening in the iluid conduit means towhich the water level sensing means is adjustably xed, the controlsensitivity of the buoyancy device and its responsiveness to maintainingitself, and any other associated device fixed to it,

at a lgiven depth beneath the surface is increased. It has been foundthat a distance in the range about it-5% of `an inch separating thewater level sensing means from the upper edge of the opening in the uidconduit provides satisfactory 'responsiveness and control with respectto maintaining the buoyancy control device at a desired depth beneaththe surface.

Referring now to FIG. l of the drawings, there is shown a free-oodingbuoyancy chamber 1i) adapted to receive and to contain an air bubble inthe upper portion thereof. Ports c are provided in the bottom ofbuoyancy chamber 10 to permit access to the interior of buoyancy chamber10 for adjustment of the equipment therein. Ports 10c also permit thewater to ow into and to flood the interior of chamber 10. Bales 11supported on spaced straps 12 are provided within the interior ofbuoyancy chamber 10 for better control of the water therein,particularly to reduce and dampen or eliminate sloshing. Air inlet ports19a and 10b are provided in the upper portion of buoyancy chamber 10,the air inlet ports -being in communication with air lines 14a and 14h,respectively, for the supply of air to buoyancy chamber 10.

Fluid conduit means or pipe 15 is provided within buoyancy chamber 10for fluid communication with the outside environment via opening 15aprovided in pipe 15. Pipe 15 by means of handle 16 is verticallyadjustable within buoyancy chamber 10, the upper portion of pipe 15moving within stack or open cylinder 18 provided in the top of buoyancychamber 10. O-rings l are positioned between the inside of stack 18 andpipe 15 to provide a substantially uid tight seal between pipe 15 andstack 18. Bar 20 is fixed by suitable means to pipe 15 within theinterior of buoyancy chamber 10. Bar 20 serves as stop means to preventthe complete withdrawal of pipe 15 from chamber lti and adjustablysupports water level sensing means 22 which is fixed to platform 24.IPlatform 24 is vertically adjustably movable with respect to bar 20 bymeans of screw 25 which is threadedly engaged with platform 24. Asknurled knob 26 is turned screw 25 turns to move platform 2d and waterlevel sensing means 22 fixed thereto upwardly or downwardly with respectto the upper surface of bar 2t). Guide means or post 28 fixed to bar 20serves to guide platform 24 in its vertical movement as knob 26 andscrew 25 are turned. Ring or collar 28a loosely fitted `around post 28serves as stop means upon contact with the under surface of platform 24to prevent the lower end of water level sensing means from moving belowthe upper edge of opening 15a provided in pipe 15.

As illustrated in the drawings S indicates the distance separating thelower end of water level sensing means 22 and the upper edge of opening15a. This distance tends to control the sensitivity and responsivenessof the buoyancy control device. The greater the distance S the less thesensitivity and the responsiveness of the control device and the smallerthe distance S the greater the sensitivity and the responsivness of thecontrol device. In actual practice when the buoyancy control device isfixed and associated with an anti-shark cage a value for S in the rangeit-3A: of an inch has been found to provide satisfactory results fromthe point of View of sensitivity and responsiveness.

Closed stack 29 is provided on the top surface of buoyancy chamber 10for the movement and insertion of water level sensing means 22 andplatform 24 :and the associated elements as water level sensing means 22is moved upwardly with respect to bar 20.

Cable 30 electrically connected with the upper end of Water levelsensing means 22 extends therefrom through the bottom of buoyancychamber 10 via opening 10d to a suitable electrical circuit and anelectric power means, such as a battery.

The overall arrangement of the elements of the buoyancy control systemis schematically illustrated in FIG. 2. In FIG. 2` cable 30 iselectrically connected to a suitable electrical circuit 31 andassociated electrical power means or battery pack 37. The electricalcircuit serves to operate and to control the operation of solenoids 32which open or close air valves 34 which control the flow of air to pipes14a for supplying air to buoyancy chamber 10 via inlet ports 10a. Airsupply means, such as air bottles 35 only one of which is in use at atime the other being held in reserve, are in uid communication viaconduits 36 and 38 to pipes 14a and 14]). Valves 34a are manuallyoperated for the supply of air via ports 1tlb and pipes 14h to chamber10 to purge chamber 1t) of water, and thereby increase buoyancy forupward movement of the assembly to the surface, in the event of anemergency.

In the operation of the buoyancy control device illustrated in thedrawings, and in particular FIGS. l and 2 thereof, the buoyancy controldevice, such as fixed to an anti-shark cage as illustrated in FIG. 3, isbrought out to a suitable location and with pipe 15 pulled down suchthat opening 15a is at its lowest level within buoyancy chamber 1t),that is the buoyancy device being set for maximum buoyancy, the buoyancydevice and associated equipment fixed thereto, e.g. the anti-shark cage,is tipped overboard. Upon being tipped overboard air is usuallyentrapped within buoyancy chamber 1? to help maintain the buoyancychamber and the cage in an upright oating position. Sufficient buoyancy,however, is already provided by the entire assembly to maintain itfloating even if buoyancy chamber 1G is completely flooded.

' Thereupon, when desired, pipe 15 is moved upwardly within buoyancychamber 10. As pipe 15 is moved upwardly within buoyancy chamber 1Gopening 15a penetrates into vthe air bubble within the buoyancy chamberand air is discharged via opening 15a and pipe 15 into the surroundingenvironment. As air is discharged the water level of the air-waterinterface of the bubble within buoyancy chamber 10 moves upwardly untilthe Water level contacts water level sensing means 22. The water, uponcontacting water level sensing means 22 which may be oat actuated oractuated by the electrical conductivity of the water, activates theelectrical control circuits to move solenoids 32 to open valves 34 topermit the flow of air from one of air tanks 35 via lines 36, 3S and 14a-and ports 10a into the upper portion of buoyancy charnber 10i. Theentry of air into buoyancy chamber 10 continues until the now growingair bubble moves the air- Water interface below the bottom of waterlevel sensing means 22. When this occurs and the supply of air is shutoff by the closing of solenoid valves 34 the air bubble within buoyancychamber 1t) is now stabilized such that the air-water interface isintermediate between the lower end of water level sensing means 22 andthe upper edge of opening 15a in pipe 15. This condition, when the lairbubble within buoyancy chamber 10 is of a sufficient size to maintainthe entire assembly in equilibrium, neutral buoyancy, beneath thesurface of the water results in the buoyancy control device maintainingitself and the associated equipment, such as the anti-shark cage, at agiven depth beneath the surface. From time to time due to wave action orother outside influences upon the buoyancy control system air may bedischarged from or introduced into the buoyancy control system in themanner indicated while the buoyancy control system maintains itself inequilibrium at a given depth.

Should it be desired to move the buoyancy control system and assembly togreater depth pipe 15 is moved upwardly within buoyancy control chamber10 causing opening 15a to discharge air into the surroundingenvironment, thereby reducing the size of the air bubble and loweringthe buoyancy to cause the entire assembly to sink to a lower level. Whenthe desired lower level is reached the air bubble is increased in sizeby moving pipe 15 downwardly until the air bubble within chamber 10 isof the size found to impart equilibrium or neutral buoyancy to theassembly.

If it is desired to move the buoyancy control system and entire assemblyupwardly closer to the surface pipe is pulled downwardly within buoyancycontrol charnber 10 causing water level sensing means 22 to come intocontact with the water below the air-water interface of the bubblewithin buoyancy chamber 10. Thereupon, the water level sensing meansactuates solenoids 32 to open valves 34 to introduce more air intobuoyancy chamber 10, increasing the size of the air bubble therein andthe buoyant power or buoyancy of the device and causing the assembly tomove upwardly to a new, higher level. As indicated hereinabove, theintroduction of air continues until the water level of the air-waterinterface of the bubble within buoyancy chamber 10 clears or isdisplaced downwardly from contact with water level sensing means 22. Theassembly can again be stabilized at this new, higher level by adjustingthe size of the air bubble to that size found to impart equilibrium orneutral buoyancy to the entire assembly.

Referring now to FIGS. 3 and 4 of the drawings, which illustrate thebuoyancy control device in accordance with this invention fixed to and/or embodied in an antishark cage or similar protective submarineobservation platform, in FIGS. 3 and 4 the same reference numerals havebeen employed as were employed in FIGS. 1 and 2 to identify the sameelements of the system. As illustrated in FIGS. 3 and 4 buoyancy chamber10 is iixed to the anti-shark cage, generally indicated by referencenumeral 40. One or more means for ingress and egress, such as door 45,is provided on the side of the shark cage. Floats 46 are fixed to thetop side edges of the shark cage to provide positive buoyancy. Asillustrated in FIG. 4 floats 46 are iilled with foamed plastic material48 to assure buoyancy even when iioats 46 are punctured. In use, ballastwould be brought into the anti-shark cage by its users to overcome thepositive buoyancy provided by floats 46. The buoyancy provided by thecontrol system would then be controlling.

Air bottles 35 are provided at the opposite corners of the shark cage.Air bottles 35 are in iiuid communication via lines 36 and -38 withlines 14a and 14b for the discharge of air into the upper portion ofbuoyancy chamber 10. In actual use only one of air bottles 35 would beoperative. The other is held in reserve.

As indicated in FIG. 3, electrical control circuit 31 in electricalcommunication with the water level sensing means and solenoids 32 aremounted on the back of panel 48 iixed to the inside of anti-shark cage40.

Although the buoyancy control system of this invention is illustrated inFIGS. 3 and 4 as being embodied in an anti-shark cage and althoughemphasis has been placed in this disclosure on the applicability and theassociation of the buoyancy control device of this invention with ananti-shark cage, various other devices may be associated with and embodythe buoyancy control system of this invention. Such devices include amine or warhead operative in association with the buoyancy controlsystem to be maintained at a given and/ or variable depth beneath thesurface of a body of water. In the application of the buoyancy controlsystem with a mine or warhead, means, such as timing means, and/orpressure or depthsensing means can be employed to actuate fluid conduitmeans or pipe 1S to cause the mine or warhead and buoyancy contol systemto be maintained at a given depth or at a variable depth depending uponthe instructions programmed into the timing device and/or depthsensingdevice associated with and controlling the buoy- `ancy control system.Instead of a mine or warhead an underwater camera might be aixed to thebuoyancy control system or an underwater prospecting device, such as ameans for determining and measuring the earths magnetic field. Numerousother devices may be employed in association with the buoyancy controlsystem of this invention.

Further, although emphasis has been placed in this disclosure on the useof air as the gaseous medium used in the buoyancy chamber any suitablegas might be employed, such as oxygen, or an oxygen-containing gas, e.g.oxygen-helium mixtures, and even non-oxygen-containing gases, such ashelium and nitrogen, provided such gases are suitable for use in thesystem, e.g. do not exhibit too great a solubility in water or similaraqueous fluids and/or are substantially non-reactive with respectthereto.

As will be apparent to those skilled in the art in the light of theforegoing disclosure, many modifications, alterations and substitutionsare possible in the practice of this invention without departing fromthe spirit or scope thereof.

I claim:

1. In a buoyancy control system wherein the size of an air bubble withina free-flooding buoyancy chamber is used to control buoyancy, theimprovement which comprises controlling the size of the air bubblewithin said buoyancy chamber by means of an adjustable water levelsensing means provided within said chamber, said water level sensingmeans being operatively connected to an air supply means and beingeffective to introduce air into said chamber from said air supply meanswhen the water of the air-water interface of said bubble within saidchamber contacts said water level sensing means and wherein said waterlevel sensing means is fixed to a iiuid conduit means associated withsaid chamber to provide fluid communication between the interior of saidchamber via an opening provided by said iiuid conduit means and theenvironment surrounding said chamber, said opening being provided inthat portion of said iiuid conduit means within said chamber, said fluidconduit means being vertically movable within said chamber and whereinsaid water level sensing means is spaced above the upper edge of saidopening provided in said fluid conduit means.

2. In a buoyancy control system in accordance with claim 1 wherein saidwater level sensing means is `adjustably fixed to said fluid conduitmeans associatedwith said chamber to provide iiuid communication betweenthe interior of said chamber via said opening provided by said Huidconduit means and the environment surrounding said chamber, saidadjustable water level sensing means being vertically adjustable withrespect to the upper edge of said opening and stop means to prevent saidwater level sensing means from vbeing positioned below the upper edge ofsaid opening.

3. In a buoyancy control system in accordance with claim 2 wherein saidair is introduced into the upper portion of said chamber to provide saidair bubble within said chamber.

4. A buoyancy control system in accordance with claim 1 wherein said airis introduced into the upper portion of said chamber to provide said airbubble within said chamber.

5. A buoyancy lcontrol system comprising a buoyancy chamber providedwith an opening in the bottom thereof for iiuid communication with theenvironment surrounding said chamber, said chamber being adapted toreceive and to contain air introduced thereinto for the formation of anair bubble within said chamber, said air bubble within said chamberbeing characterized by an air-water interface, fluid conduit meansassociated with said chamber to provide fluid communication between theinterior of said chamber and said surrounding environment, said Huidconduit means being vertically movable within said chamber and providedwith an opening for effecting Huid communication via said fluid conduitmeans between the interior of said chamber and said environmentsurrounding said chamber, water level sensing means fixed to said uidconduit means and movable therewith within said chamber, said waterlevel sensing means being spaced above the upper edge of said openingprovided by said air supply means for the introduction of air into saidchamber when said water level sensing means contacts the water at saidair-water interface Within said chamber.

6. A buoyancy control system in accordance with claim wherein said waterlevel sensing means is adjustably xed to said uid conduit means.

7. A buoyancy control system in accordance with claim 5 wherein saidwater level sensing means is adjustably xed to said fluid conduit meansand wherein stop means is provided to prevent said water level sensingmeans from being positioned below the upper edge of said opening.

8. A buoyancy control system in accordance with claim 5 wherein the airis introduced into said chamber within the upper portion thereof.

9. A buoyancy control system in accordance with claim 5 wherein saidfluid conduit means extends above the top of and below the bottom ofsaid chamber, said opening being provided intermediate the ends of saidfluid conduit means.

10. A buoyancy control system in accordance with claim 9 wherein ahandle is provided at that end of the fluid conduit means extendingbelow the bottom of said chamber for vertically adjusting the positionof said opening within the interior of said chamber together with saidwater level sensing means.

11. A buoyancy control system in accordance with claim 9 wherein ahandle is provided at that end of the fluid conduit means extendingbelow the bottom of said chamber for vertically adjusting the positionof said opening within the interior of said chamber together with saidwater level sensing means, and stop means effective to prevent thewithdrawal of said fluid conduit means from said chamber.

12. A buoyancy control system in accordance with claim 5 wherein stopmeans are provided to prevent the withdrawal of said fluid conduit meansfrom said chamber.

13. An anti-shark cage or similar structure comprising a cage providedwith means for egress therefrom and ingress thereto, a plurality ofpositive buoyancy bodies or floats ixed along the upper edges of saidcage on the outside thereof, a buoyancy chamber fixed to the outside topof said cage, said buoyancy chamber being provided with an opening inthe bottom thereof for uid communication with the environmentsurrounding said chamber, said chamber being adapted to receive and tocontain air introduced thereinto for the formation of an air bubblewithin said chamber, said air bubble within said charnber beingcharacterized by an air-water interface, fiuid conduit means associatedwith said chamber to provide fluid communication between the interior ofsaid chamber and said surrounding environment, said fluid conduit meansbeing vertically movable within said chamber and extending downwardlyinto said cage, the end of said fluid conduit means within said cagebeing provided with a handle for eiecting vertical movement of said uidconduit means, said uid conduit means also being provided with anopening for eecting iluid communication via said fluid conduit meansbetween the interior of said chamber and said environment surroundingsaid chamber, water level sensing means Xed to said fluid conduit meansand movable therewith within said chamber, said Water level sensingmeans being adjustably spaced above the upper edge of said openingprovided by said uid conduit means, air supply means and meansoperatively connecting said water level sensing means and said airsupply means for the introduction of air into said chamber when saidwater level sensing means Contacts the water of said air-water interfacewithin said chamber.

References Cited UNITED STATES PATENTS MILTON BUCHLER, Primary Examiner.

T. M. BLIX, Assistant Examiner.

1. IN A BUOYANCY CONTROL SYSTEM WHEREIN THE SIZE OF AN AIR BUBBLE WITHINA FREE-FLOODING BUOYANCY CHAMBER IS USED TO CONTROL BUOYANCY, THEIMPROVEMENT WHICH COMPRISES CONTROLLING SIZE OF THE AIR BUBBLE WITHINSAID BUOYANCY CHAMBER BY MEANS OF AN ADJUSTABLE WATER LEVEL SENSINGMEANS PROVIDED WITHIN SAID CHAMBER, SAID WATER LEVEL SENSING MEANS BEINGOPERATIVELY CONNECTED TO AN AIR SUPPLY MEANS AND BEING EFFECTIVE TOINTRODUCE AIR INTO SAID CHAMBER FROM SAID AIR SUPPLY MEANS WHEN THEWATER OF THE AIR-WATER INTERFACE OF SAID BUBBLE WITHIN SAID CHAMBERCONTACTS SAID WATER LEVEL SENSING MEANS AND WHEREIN SAID WATER LEVELSENSING MEANS IS FIXED TO A FLUID